TW201726949A - Heat treatment method and heat treatment device - Google Patents

Abstract

A susceptor is preheated through light irradiation by a halogen lamp before the first semiconductor wafer of a lot as a processing target is transferred into a chamber. The temperature of the susceptor is measured by a radiation thermometer. A control unit is configured to control the output of the halogen lamp so that the temperature of the susceptor reaches a stable temperature based on a result of the measurement of the temperature of the susceptor by the radiation thermometer. The stable temperature of the susceptor is the temperature of the susceptor when the temperature of the susceptor is risen to a constant temperature by continuously performing light irradiation heating on a plurality of semiconductor wafers in the chamber without heating the susceptor.

Description

Heat treatment method and heat treatment device

The present invention relates to a heat treatment method and a heat treatment apparatus for heating a thin plate-shaped precision electronic substrate (hereinafter simply referred to as a "substrate") such as a semiconductor wafer to heat the substrate.

In the fabrication process of a semiconductor device, impurity introduction is a step required to form a pn junction in a semiconductor wafer. Currently, impurity introduction is generally carried out using an ion implantation method and its subsequent annealing method. The ion implantation method is a technique for ionizing elements of impurities such as shed (B), arsenic (As), and phosphorus (P) and causing them to collide with a semiconductor wafer at a high acceleration voltage to physically implant impurities. . The implanted impurities are activated by annealing treatment. At this time, when the annealing time is several seconds or more, the implanted impurities are deeply diffused by the heat energy, and as a result, the joint depth is deeper than required, which affects the formation of a good device.

Therefore, in recent years, flash lamp anneal (FLA) has attracted attention as an annealing technique for heating a semiconductor wafer in a very short time. Flash lamp annealing is a heat treatment technique that uses a xenon flash lamp (hereinafter referred to as a "flash" to refer to a flash lamp) to illuminate the surface of a semiconductor wafer. Flashing, whereby only the surface of the semiconductor wafer into which the impurities have been implanted is heated within a very short time (below milliseconds).

The emission spectrum of the xenon flash lamp is from the ultraviolet region to the near-infrared region, and the wavelength is shorter than the wavelength of the conventional halogen lamp, and approximately coincides with the basic absorption band of the germanium semiconductor wafer. Therefore, when the semiconductor wafer is irradiated with a flash from the xenon flash lamp, the amount of transmitted light is small, and the semiconductor wafer can be rapidly heated. Further, it is known that only a short-time flash irradiation of several milliseconds or less can selectively increase the temperature of the vicinity of the surface of the semiconductor wafer. Therefore, as long as the temperature rise is extremely short for the xenon flash lamp, the impurities are not diffused deeply, and only the impurity activation can be performed.

As a heat treatment apparatus using such a xenon flash lamp, Patent Literatures 1 and 2 disclose that a pulse emitting lamp such as a flash lamp is disposed on the surface side of the semiconductor wafer, and a halogen lamp or the like is disposed on the back side. The lamps are continuously lit, and the desired heat treatment is performed by such a combination. In the heat treatment apparatus disclosed in Patent Documents 1 and 2, the semiconductor wafer is preheated by a halogen lamp or the like until it reaches a certain temperature, and then heated by the pulse wave from the flash lamp to reach a desired processing temperature.

[Previous Technical Literature]

[Patent Literature]

Patent Document 1: Japanese Laid-Open Patent Publication No. SHO 60-258928.

Patent Document 2: Japanese Laid-Open Patent Publication No. 2005-527972.

In general, it is not limited to heat treatment, and the processing of the semiconductor wafer is a lot (the object that performs the same processing under the same conditions) The set of semiconductor wafers is performed in units. In the blade type substrate processing apparatus, the semiconductor wafers constituting the plurality of sheets of the batch are sequentially processed in order. In the flash lamp annealing apparatus, a plurality of semiconductor wafers constituting a batch are also carried into a chamber one by one and sequentially heat-treated.

In the case where the flash annealing apparatus in the stopped state starts the batch processing, the initial semiconductor wafer of the batch is carried into the chamber at about room temperature and heat-treated. During the heat treatment, the semiconductor wafer supported by the carrier in the chamber is preheated to a predetermined temperature, and the surface of the wafer is heated to a processing temperature by flash heating. As a result, heat is transferred from the heated semiconductor wafer to the cavity structure such as the carrier, and the temperature of the carrier or the like also rises. The temperature rise of the carrier or the like accompanying the heat treatment of the semiconductor wafer continues from a few times from the beginning of the batch until the heat treatment of the semiconductor wafer of about tenth wafer is performed, and the temperature of the carrier reaches. A certain stable temperature. That is, the first semiconductor wafer of the batch is supported and processed by the room temperature carrier; in contrast, the semiconductor wafer after the tenth wafer is supported and processed by the carrier that has been heated to a stable temperature.

Therefore, the temperature at which a plurality of semiconductor wafers constituting the batch are generated is inconsistent. In particular, for a plurality of semiconductor wafers from the beginning of the batch, the semiconductor wafer is supported and processed by the lower temperature carrier, so that the surface reaching temperature at the time of flash irradiation does not reach the processing temperature. In addition, when a semiconductor wafer supported by a low-temperature carrier is irradiated with a flash, wafer warpage may occur due to a temperature difference between the carrier and the semiconductor wafer, and as a result, the semiconductor wafer may be damaged.

Therefore, in the past, before the start of batch processing, the following operation (dummy running) is performed: a dummy wafer that is not a processing target The dummy wafer is carried into the chamber and supported by the carrier, and the flash heat treatment is performed under the same conditions as the batch to be processed, whereby the chamber structure such as the carrier is heated in advance. Since the carrier is moved to a stable temperature by performing the flash heat treatment on about ten or so dummy wafers, the processing of the first semiconductor wafer to be processed is started. In this way, the temperature history of the plurality of semiconductor wafers constituting the batch becomes uniform, and the wafer warpage caused by the temperature difference between the carrier and the semiconductor wafer can be prevented.

However, since such a simulation operation not only consumes a dummy wafer that is not related to the processing, but also requires a flash heating process for ten or so simulated wafers, there is a problem that the efficiency of the flash annealing device is hindered.

The present invention has been made in view of the above problems, and an object thereof is to provide a heat treatment method and a heat treatment apparatus capable of omitting a simulation operation.

In order to solve the above problems, the invention of the first aspect is a heat treatment method for heating a substrate by irradiating light onto the substrate. The heat treatment method includes a carrying step of carrying the substrate into the chamber and placing the substrate on the carrier. a light irradiation step of irradiating light onto a substrate that has been placed on the carrier; and a temperature measuring step of measuring a temperature of the carrier before the first substrate of the batch is carried into the chamber; and a heating step The foregoing carrier is heated in accordance with the measurement result of the aforementioned temperature measuring step.

Further, in the invention of the second aspect of the invention, in the heat treatment method of the invention of the first aspect, the plurality of substrates of the batch are continuously irradiated with light and heated without heating the carrier, whereby the carrier is provided. Temperature The temperature of the carrier is set to a stable temperature when the degree is increased, and in the heating step, the carrier is heated such that the temperature of the carrier reaches the stable temperature.

According to a third aspect of the invention, in the heat treatment method of the first aspect, the temperature of the plurality of portions of the carrier is measured in the temperature measuring step; and each of the plurality of portions is included in the heating step. Each zone is heated for control.

Further, in the heat treatment method of the invention of the first aspect, in the light irradiation step, the substrate is irradiated with a flash from the side of the chamber by a flash lamp.

According to a fifth aspect of the invention, in the heat treatment method of the invention of the fourth aspect, in the light irradiation step, the substrate is further irradiated with light by a halogen lamp from the other side of the chamber; The carrier is heated by irradiation of light from a halogen lamp.

In addition, the invention of the sixth aspect is a heat treatment apparatus for irradiating light onto a substrate to heat the substrate; the heat treatment apparatus includes: a chamber for accommodating the substrate; and a carrier disposed in the chamber for Mounting and supporting the substrate; the light-irradiating portion irradiates light onto the substrate placed on the carrier; the temperature measuring unit measures the temperature of the carrier; and the control unit is carried in the first substrate of the batch Before the chamber, the light irradiation unit is controlled such that the light is irradiated by the light from the light irradiation unit to heat the carrier according to the measurement result of the temperature of the carrier measured by the temperature measuring unit.

Further, the invention of the embodiment 7 is in the heat of the invention of the embodiment 6 In the processing apparatus, it is not necessary to heat the carrier, but the plurality of substrates of the batch are continuously irradiated with light from the light irradiation unit and heated, whereby the temperature of the carrier is increased and the carrier is fixed for a certain period of time. The temperature is set to a stable temperature, and the control unit controls the light irradiation unit such that the temperature of the carrier reaches the stable temperature.

According to a sixth aspect of the invention, in the heat treatment apparatus of the aspect of the invention, the temperature measuring unit includes: a plurality of temperature sensors for measuring a temperature of a plurality of portions of the carrier; the control The portion controls the light irradiation from the light-irradiating portion for each of the regions including the plurality of the plurality of portions.

According to a still further aspect of the invention, in the heat treatment device of the aspect of the invention, the light-irradiating portion includes a flash lamp that illuminates the substrate from a side of the chamber.

According to a tenth aspect of the invention, in the heat treatment apparatus of the aspect of the invention, the light-irradiating portion further includes: a halogen lamp that irradiates the substrate with light from the other side of the chamber; The light of the halogen lamp is irradiated to heat the carrier.

According to the invention of the first aspect to the fifth aspect, since the temperature of the carrier is measured before the initial substrate of the batch is carried into the chamber and the carrier is heated according to the measurement result, the simulation can be constructed even if the simulation operation is omitted. The temperature of the entire substrate of the batch was consistent.

In particular, according to the invention of the third aspect, since the temperature of the plurality of parts of the carrier is measured and each of the plurality of parts is included The area is heated and controlled so that the heating accuracy of the carrier can be improved.

According to the invention of the sixth aspect to the embodiment 10, since the measurement result of the temperature of the carrier measured by the temperature measuring portion before the initial substrate of the batch is carried into the chamber is irradiated with light from the light irradiation portion Since the carrier is heated, even if the simulation operation is omitted, the temperatures of all the substrates constituting the batch can be made uniform.

In particular, according to the invention of the eighth aspect, since the temperature of the plurality of portions of the carrier is measured and each region including the plurality of portions is controlled to irradiate light from the light-irradiating portion, the carrier can be Increased heating accuracy.

1‧‧‧ Heat treatment unit

3‧‧‧Control Department

4‧‧‧Halogen heating department

5‧‧‧Flash heating department

6‧‧‧ chamber

7‧‧‧ Keeping Department

10‧‧‧Transportation mechanism

11‧‧‧Transfer arm

12‧‧‧Departure

13‧‧‧Horizontal mobile agency

14‧‧‧ Lifting mechanism

27, 120‧‧‧ radiation thermometer

31‧‧‧ Pulse Generator

32‧‧‧ Waveform setting section

33‧‧‧ Input Department

41, 51‧‧‧ frame

43, 52‧‧‧ reflector

53‧‧‧Lighting window

61‧‧‧ side of the chamber

62‧‧‧ recess

63‧‧‧Upper chamber window

64‧‧‧Lower chamber window

65‧‧‧ Heat treatment space

66‧‧‧Transportation opening

68, 69‧‧‧ reflection ring

71‧‧‧Base ring

72‧‧‧Connecting Department

74‧‧‧Carrier

76‧‧‧ Guide pin

77‧‧‧Incision Department

78‧‧‧ openings

79‧‧‧through holes

81‧‧‧ gas supply hole

82, 87‧‧‧ buffer space

83‧‧‧ gas supply pipe

84, 89, 192‧‧ ‧ valves

85‧‧‧Nitrogen supply

86‧‧‧ gas vents

88, 191‧‧‧ gas exhaust pipe

91‧‧‧ trigger electrode

92‧‧‧ glass tube

93‧‧‧ capacitor

94‧‧‧Inductors

95‧‧‧Power unit

96‧‧‧IGBT

97‧‧‧ trigger circuit

130‧‧‧Contact thermometer

185‧‧‧ gate valve

190‧‧‧Exhaust Department

CZ‧‧‧ central section

EZ‧‧‧ Peripheral section

FL‧‧‧Flash

HL‧‧‧ halogen lamp

MZ‧‧‧ middle section

W‧‧‧Semiconductor Wafer

Fig. 1 is a longitudinal sectional view showing the configuration of a heat treatment apparatus of the present invention.

Fig. 2 is a perspective view showing the overall appearance of the holding portion.

Fig. 3 is a plan view of the holding portion viewed from above.

Fig. 4 is a side view of the holding portion viewed from the side.

Figure 5 is a plan view of the transfer mechanism.

Figure 6 is a side view of the transfer mechanism.

Fig. 7 is a plan view showing the configuration of a plurality of halogen lamps.

Fig. 8 is a view showing a driving circuit of a flash lamp.

Fig. 9 is a view showing the relationship between the number of processed semiconductor wafers and the temperature of the carrier.

Fig. 10 is a view showing an example of zone control showing the temperature of the carrier.

Embodiments of the present invention will be described in detail below with reference to the drawings.

<First Embodiment>

Fig. 1 is a longitudinal sectional view showing the configuration of a heat treatment apparatus 1 of the present invention. The heat treatment apparatus 1 of the present embodiment is a flash lamp annealing apparatus that heats the semiconductor wafer W by performing flash irradiation on a wafer-shaped semiconductor wafer W as a substrate. The size of the semiconductor wafer W to be processed is not particularly limited, and is, for example, ψ300 mm or ψ450 mm. The semiconductor wafer W before being carried into the heat treatment apparatus 1 is implanted with impurities, and the heat treatment is performed by the heat treatment apparatus 1 to perform activation treatment of the implanted impurities. In addition, in FIG. 1 and subsequent figures, in order to make it easy to understand, the size and number of each part are required to be exaggerated or simplified.

The heat treatment apparatus 1 includes a chamber 6 for accommodating a semiconductor wafer W, a flash heating unit 5 for internally incorporating a plurality of flash lamps FL, and a halogen heating unit 4 for internally incorporating a plurality of halogen lamps HL. A flash heating portion 5 is provided on the upper side of the chamber 6, and a halogen heating portion 4 is provided on the lower side of the chamber 6. Further, the heat treatment apparatus 1 is provided inside the chamber 6 with a holding portion 7 for holding the semiconductor wafer W in a horizontal posture, and a transfer mechanism 10 for performing a semiconductor wafer between the holding portion 7 and the outside of the device. W's acceptance. Further, the heat treatment apparatus 1 includes a control unit 3 that controls the operation of the halogen wafer heating unit 4, the flash heating unit 5, and the chamber 6 to perform heat treatment of the semiconductor wafer W.

The chamber 6 is formed by attaching a quartz chamber window to the upper and lower sides of the cylindrical chamber side portion 61. The chamber side portion 61 has a substantially cylindrical shape in which the upper and lower chamber windows 63 are opened at the upper side, and the lower chamber window 64 is attached to the lower side to be closed. The upper chamber window 63 constituting the top plate portion of the chamber 6 is a disk-shaped member formed of quartz, and serves as a quartz window that penetrates the flash light emitted from the flash heating portion 5 into the chamber 6. Play a role. Further, the lower chamber window 64 constituting the bottom plate portion of the chamber 6 is also a disk-shaped member formed of quartz, and functions as a quartz window that penetrates the light from the halogen heating portion 4 into the chamber 6. effect.

Further, a reflection ring 68 is attached to an upper portion of the inner wall surface of the chamber side portion 61, and a reflection ring 69 is attached to the lower portion. The reflection rings 68, 69 are all formed in an annular shape. The upper reflection ring 68 is attached by being fitted from the upper side of the chamber side portion 61. On the other hand, the lower reflection ring 69 is fitted from the lower side of the chamber side portion 61 and is locked by a bolt (not shown). That is, the reflection rings 68, 69 are detachably attached to the chamber side portion 61. The inner space of the chamber 6, that is, the space surrounded by the upper chamber window 63, the lower chamber window 64, the chamber side portion 61, and the reflection rings 68, 69 is defined as the heat treatment space 65.

Reflecting rings 68, 69 are provided in the chamber side portion 61, whereby a recess 62 is formed in the inner wall surface of the chamber 6. That is, the central portion of the inner wall surface of the chamber side portion 61 where the reflection rings 68, 69 are not provided, the lower end surface of the reflection ring 68, and the concave portion 62 surrounded by the upper end surface of the reflection ring 69 are formed. The concave portion 62 is formed in an annular shape in the horizontal direction on the inner wall surface of the chamber 6, and surrounds the holding portion 7 for holding the semiconductor wafer W.

The chamber side portion 61 and the reflection rings 68 and 69 are formed of a metal material (for example, stainless steel) excellent in strength and heat resistance. Further, the inner circumferential surfaces of the reflection rings 68 and 69 are mirror-coated by electrolytic nickel plating.

Further, a chamber opening portion 61 is formed with a conveyance opening portion (furnace port) 66 for carrying in and carrying out the semiconductor wafer W to the chamber 6. The conveyance opening portion 66 is formed to be openable and closeable by the gate valve 185. Handling opening 66 The connection is connected to the outer peripheral surface of the recess 62. Therefore, when the gate valve 185 opens the transport opening 66, the semiconductor wafer W can be carried into the heat treatment space 65 through the recess 62 from the transport opening 66, and the semiconductor wafer W can be carried out from the heat treatment space 65. Further, when the gate valve 185 closes the conveyance opening portion 66, the heat treatment space 65 in the chamber 6 serves as a sealed space.

Further, a gas supply hole 81 for supplying a processing gas (nitrogen (N ₂ ) in the present embodiment) to the heat treatment space 65 is formed in the upper portion of the inner wall of the chamber 6. The gas supply hole 81 is formed at a position above the concave portion 62 and may be provided on the reflection ring 68. The gas supply hole 81 is connected to the gas supply pipe 83 via a buffer space 82 formed annularly inside the side wall of the chamber 6. The gas supply pipe 83 is connected to the nitrogen supply source 85. Further, a valve 84 is interposed in the middle of the path of the gas supply pipe 83. When the valve 84 is open, nitrogen gas is supplied from the nitrogen supply source 85 to the buffer space 82. The nitrogen gas that has flowed into the buffer space 82 flows so as to diffuse in the buffer space 82 having a smaller fluid impedance than the gas supply hole 81, and is supplied from the gas supply hole 81 into the heat treatment space 65. Further, the processing gas is not limited to nitrogen gas, and may be an inert gas such as argon (Ar) or helium (He); or may be oxygen (O ₂ ), hydrogen (H ₂ ), chlorine (Cl ₂ ), or hydrogen chloride ( A reactive gas such as HC _l ), ozone (O ₃ ), or ammonia (NH ₃ ).

On the other hand, a gas exhaust hole 86 for exhausting the gas in the heat treatment space 65 is formed in the lower portion of the inner wall of the chamber 6. The gas exhaust hole 86 is formed at a position lower than the recess 62 and may be provided on the reflection ring 69. The gas exhaust hole 86 is connected to the gas exhaust pipe 88 via a buffer space 87 formed annularly inside the side wall of the chamber 6. The gas exhaust pipe 88 is connected to the exhaust portion 190. Further, a valve 89 is interposed in the middle of the path of the gas exhaust pipe 88. When the valve 89 is opened, the gas system of the heat treatment space 65 is discharged from the gas vent hole 86 to the gas row via the buffer space 87. Air tube 88. Further, the gas supply hole 81 and the gas exhaust hole 86 may be provided in plural in the circumferential direction of the chamber 6, or may be in the form of a straight slit. Further, the nitrogen gas supply source 85 and the exhaust portion 190 may be a mechanism provided in the heat treatment apparatus 1, or may be a utility of a factory provided in the heat treatment apparatus 1.

Further, a gas exhaust pipe 191 for discharging the gas in the heat treatment space 65 is also connected to the front end of the conveyance opening portion 66. The gas exhaust pipe 191 is connected to the exhaust portion 190 via a valve 192. The valve 192 is opened, whereby the gas in the chamber 6 is exhausted via the conveying opening portion 66.

FIG. 2 is a perspective view showing the overall appearance of the holding portion 7. 3 is a plan view of the holding portion 7 viewed from above, and FIG. 4 is a side view of the holding portion 7 as viewed from the side. The holding portion 7 is configured to include a base ring 71, a coupling portion 72, and a susceptor 74. The abutment ring 71, the coupling portion 72, and the carrier 74 are all formed of quartz. That is, the entirety of the holding portion 7 is formed of quartz.

The abutment ring 71 is a ring-shaped quartz member. The base ring 71 is placed on the bottom surface of the recess 62, thereby being supported by the wall surface of the chamber 6 (see Fig. 1). A plurality of connecting portions 72 (four in the present embodiment) are provided on the upper surface of the abutment ring 71 having a circular ring shape along the circumferential direction thereof. The connecting portion 72 is also a quartz member and is fixed to the base ring 71 by welding. Further, the shape of the abutment ring 71 may be an arc shape in which the annular shape lacks a part.

The flat carrier 74 is supported by the four connecting portions 72 provided on the base ring 71. The carrier 74 is a substantially circular flat member formed of quartz. The diameter of the carrier 74 is larger than the diameter of the semiconductor wafer W. That is, the carrier 74 has a larger planar size than the semiconductor wafer W. A plurality of (in the present embodiment, five) quide pins 76 are erected on the upper surface of the carrier 74. The five guide pins 76 are concentric with the outer circumference of the carrier 74. Set on the circumference. The diameter of the circle in which the five guide pins 76 are disposed is slightly larger than the diameter of the semiconductor wafer W. Each of the guide pins 76 is also formed of quartz. Further, the guide pin 76 may be integrally formed of an ingot of quartz with the carrier 74, or the additional guide pin 76 may be attached to the carrier 74 by welding or the like.

The four connecting portions 72 that are erected on the base ring 71 and the lower surface of the peripheral portion of the carrier 74 are fixed by welding. That is, the carrier 74 and the base ring 71 are fixedly coupled by the connecting portion 72; the holding portion 7 is an integrally formed member of quartz. The base ring 71 of the holding portion 7 is supported by the wall surface of the chamber 6, so that the holding portion 7 is attached to the chamber 6. In a state in which the holding portion 7 is attached to the chamber 6, the substantially round-plate-shaped carrier 74 is in a horizontal posture (a posture in which the normal line coincides with the vertical direction). The semiconductor wafer W carried into the chamber 6 is placed and held in a horizontal posture on the carrier 74 that has been attached to the holding portion 7 of the chamber 6. The semiconductor wafer W is placed on the inner side of a circle formed by the five guide pins 76, thereby preventing positional deviation in the horizontal direction. Further, the number of the guide pins 76 is not limited to five, as long as the number of positions of the semiconductor wafer W can be prevented from deviating.

Further, as shown in FIGS. 2 and 3, an opening portion 78 and a notch portion 77 that penetrate vertically are formed in the carrier 74. The notch portion 77 is provided to pass the probe tip end portion of the contact thermometer 130 using the thermocouple. On the other hand, the opening portion 78 is provided to allow the radiation thermometer 120 to receive the emitted light (infrared light) emitted from the lower surface of the semiconductor wafer W held by the carrier 74. Further, the carrier 74 is provided with four through holes 79 for allowing the lift pins 12 of the transfer mechanism 10 to be described later to pass through the semiconductor wafer W. In addition, the radiation temperature Both the meter 120 and the contact thermometer 130 are thermometers for measuring the temperature of the semiconductor wafer W, and are not for measuring the temperature of the holding portion 7 including the carrier 74.

FIG. 5 is a plan view of the transfer mechanism 10. In addition, FIG. 6 is a side view of the transfer mechanism 10. The transfer mechanism 10 is provided with two transfer arms 11. The transfer arm 11 is formed in an arc shape approximately along the annular recess 62. Two lift pins 12 are erected on each of the transfer arms 11 . Each of the transfer arms 11 is configured to be rotatable by the horizontal movement mechanism 13. The horizontal movement mechanism 13 horizontally moves the pair of transfer arms 11 with respect to the holding portion 7 between the transfer operation position (the solid line position in FIG. 5) and the retracted position (the two-dot chain line position in FIG. 5). The transfer operation position is to transfer the semiconductor wafer W, and the retracted position does not overlap the semiconductor wafer W held by the holding portion 7 in a plan view. As the horizontal moving mechanism 13, a mechanism for rotating each of the transfer arms 11 by an individual motor may be used, or a pair of transfer arms 11 may be linked by a single link using a link mechanism. The mechanism of rotation.

Further, the pair of transfer arms 11 are moved up and down together with the horizontal movement mechanism 13 by the elevating mechanism 14. When the elevating mechanism 14 raises the pair of transfer arms 11 at the transfer operation position, a total of four lift pins 12 pass through the through holes 79 (see FIGS. 2 and 3) that have been bored through the carrier 74, and The upper end of the lowering pin 12 protrudes from the upper surface of the carrier 74. On the other hand, the elevating mechanism 14 lowers the pair of transfer arms 11 at the transfer operation position, takes the lift pins 12 out of the through holes 79, and opens the pair of transfer arms 11 in the horizontal movement mechanism 13 in an open manner. When moving, each of the transfer arms 11 is moved to the retracted position. The retracted position of the pair of transfer arms 11 is directly above the base ring 71 of the holding portion 7. Since the base ring 71 is placed on the bottom surface of the recess 62, the retracted position of the transfer arm 11 is the inside of the recess 62. Further, the driving unit (the horizontal moving mechanism 13 and the lifting mechanism 14) provided with the transfer mechanism 10 is provided. An exhaust mechanism (not shown) is also provided in the vicinity of the portion, and the atmosphere around the drive portion of the transfer mechanism 10 is discharged to the outside of the chamber 6.

Referring back to FIGS. 1 and 2, a radiation thermometer 27 is provided inside the chamber 6. The radiation thermometer 27 is a temperature sensor for detecting infrared light emitted from the carrier 74 of the holding portion 7 and measuring the temperature of the carrier 74. In the first embodiment, the radiation thermometer 27 is provided at a position where the temperature of the center portion of the carrier 74 can be measured.

The flash heating unit 5 provided above the chamber 6 is configured to include a light source on the inner side of the casing 51, and is composed of a plurality of flashlights FL (which are 30 in the present embodiment) belonging to a xenon flash lamp; A reflector 52 is disposed to cover the upper side of the light source. Further, a light radiation window 53 is attached to the bottom of the casing 51 of the flash heating unit 5. The light emission window 53 for constituting the bottom of the flash heating portion 5 is a plate-shaped quartz window formed of quartz. The light radiation window 53 is opposed to the upper chamber window 63 by providing the flash heating portion 5 above the chamber 6. The flash lamp FL flashes the semiconductor wafer W by flashing the heat treatment space 65 from above the chamber 6 via the light emission window 53 and the upper chamber window 63.

Each of the plurality of flash lamps FL is a rod-shaped lamp having a long cylindrical shape, and the main surface of the semiconductor wafer W held by the holding portion 7 in the longitudinal direction of each (that is, in the horizontal direction) Arranged in a plane parallel to each other. Therefore, the plane formed by the arrangement of the flash lamps FL is also a horizontal plane.

Fig. 8 is a view showing a drive circuit of the flash lamp FL. As shown in FIG. 8, the capacitor 93, the inductor 94, the flash lamp FL, and the IGBT (Insulated Gate) Bipolar Transistor; insulated gate bipolar transistor) 96 series connected in series. Further, as shown in FIG. 8, the control unit 3 includes a pulse wave generator 31 and a waveform setting unit 32, and is connected to the input unit 33. As the input unit 33, various well-known input devices such as a keyboard, a mouse, and a touch panel can be used. The waveform setting unit 32 sets the waveform of the pulse wave signal based on the input content from the input unit 33, and the pulse wave generator 31 generates a pulse wave signal based on the waveform.

The flash lamp FL is provided with a rod-shaped glass tube (discharge tube) 92, and an anode and a cathode are disposed at both end portions of the helium gas sealed therein, and a trigger electrode 91 is attached to the outer peripheral surface of the glass tube 92. . A predetermined voltage is applied to the capacitor 93 by the power supply unit 95, and the charge is charged with a voltage (charge voltage). Further, a high voltage can be applied to the trigger electrode 91 from the flip-flop circuit 97. The timing at which the trigger circuit 97 applies a voltage to the trigger electrode 91 is controlled by the control unit 3.

The IGBT 96 is a bipolar transistor in which a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) is incorporated in a gate portion, and is a switching element suitable for using a large power. A pulse wave signal is applied to the gate of the IGBT 96 from the pulse wave generator 31 of the control unit 3. When a voltage (high voltage) equal to or higher than a predetermined value is applied to the gate of the IGBT 96, the IGBT 96 is turned on (ON); when a voltage (low voltage) that is less than a predetermined value is applied, the IGBT 96 is turned off. (OFF) status. Thus, the driving circuit including the flash lamp FL is turned on and off by the IGBT 96. By the IGBT 96 being turned on and off, the connection between the flash lamp FL and the corresponding capacitor 93 is intermittent, thereby turning on and off the current flowing through the flash lamp FL.

Even when the capacitor 93 is charged, the IGBT 96 is turned on and a high voltage is applied to both ends of the glass tube 92, since helium is electrically Since the insulator is in a normal state, electrical flow does not flow in the glass tube 92 in a normal state. However, in the case where the trigger circuit 97 applies a high voltage to the trigger electrode 91 to break the insulation, a current flows instantaneously in the glass tube 92 by the discharge between the electrodes at both ends, whereby the atomic or molecular excitation of the helium gas at this time is excited. And let out the light.

The drive circuit shown in FIG. 8 is individually provided to each of the plurality of flash lamps FL that have been provided in the flash heating unit 5. In the present embodiment, since the 30 flash lamps FL are arranged in a planar shape, 30 drive circuits as shown in Fig. 8 are provided corresponding thereto.

The reflector 52 is disposed above the plurality of flash lamps FL in such a manner as to cover the entirety of the plurality of flash lamps FL. The basic function of the reflector 52 is to reflect the flash emitted from the plurality of flashers FL to the heat treatment space 65 side. The reflector 52 is formed of an aluminum alloy plate, and its surface (the surface facing the side of the flash lamp FL) is subjected to a roughening process by a blast process.

The halogen heating unit 4 provided below the chamber 6 is provided with a plurality of (40 in the present embodiment) halogen lamps HL built in the inside of the casing 41. The halogen heating unit 4 is configured to irradiate light from the lower portion of the chamber 6 to the heat treatment space 65 through the lower chamber window 64 by a plurality of halogen lamps HL to heat the light irradiation portion of the semiconductor wafer W. The halogen heating unit 4 irradiates halogen light that penetrates the carrier 74 of the quartz and is irradiated onto the lower surface of the semiconductor wafer W supported by the carrier 74.

Fig. 7 is a plan view showing the configuration of a plurality of halogen lamps HL. The 40 halogen lamps HL are divided into two sections to be arranged. 20 halogen lamps HL are disposed in the upper portion of the holding portion 7, and 20 halogen lamps HL are disposed in the lower portion of the holding portion 7 from the upper portion. Each halogen lamp HL has a length Rod-shaped rod-shaped lamp. Each of the 20 halogen lamps HL in the upper and lower stages is arranged in parallel with each other along the longitudinal direction of each of the main faces of the semiconductor wafer W held by the holding portion 7 (that is, in the horizontal direction). Therefore, the plane formed by the arrangement of the halogen lamps HL of the upper and lower sections is a horizontal plane.

Further, as shown in FIG. 7, both the upper stage and the lower stage are compared with the area facing the central portion of the semiconductor wafer W held by the holding portion 7, and the halogen lamp HL in the region facing the peripheral portion. The density of the distribution system becomes higher. That is, both the upper stage and the lower stage are: the arrangement pitch of the halogen lamps HL in the peripheral portion is shorter than the central portion of the lamp array. Therefore, it is possible to irradiate the peripheral portion of the semiconductor wafer W which is likely to cause a temperature drop when the light irradiation from the halogen heating unit 4 is heated, to a larger amount of light.

Further, the lamp group composed of the upper halogen lamp HL and the lamp group constituted by the lower halogen lamp HL are arranged in a lattice pattern. In other words, a total of 40 halogen lamps HL are disposed so that the longitudinal direction of the 20 halogen lamps HL disposed in the upper stage and the longitudinal direction of the 20 halogen lamps HL disposed in the lower stage are orthogonal to each other.

The halogen lamp HL is a filament-type light source that heats and illuminates the filament by energizing a filament disposed inside the glass tube. A gas in which a halogen element (iodine or bromine) is introduced into an inert gas such as nitrogen or argon is enclosed in the inside of the glass tube. By introducing a halogen element, it is possible to suppress the breakage of the filament and set the temperature of the filament to a high temperature. Therefore, the halogen lamp HL has a feature that the normal life is longer than that of the incandescent lamp and the glare can be continuously irradiated. That is, the halogen lamp HL is a continuous lighting lamp that continuously emits light for at least one second or more. Further, since the halogen lamp HL is a rod-shaped lamp, it has a long life and is excellent in that the halogen lamp HL is arranged in the horizontal direction. The radiation efficiency of the semiconductor wafer W above. Further, the output of the 40 halogen lamps HL can be individually adjusted by the control unit 3.

Further, in the casing 41 of the halogen heating unit 4, a reflector 43 (FIG. 1) is also provided below the two-stage halogen lamp HL. The reflector 43 reflects the light emitted from the plurality of halogen lamps HL to the heat treatment space 65 side.

The control unit 3 controls the above various operation mechanisms provided in the heat treatment apparatus 1. The hardware configuration of the control unit 3 is the same as that of a general computer. In other words, the control unit 3 is configured to include a CPU (Central Processing Unit) and a circuit for performing various types of arithmetic processing, and a ROM (Read Only Memory) for storing basics. Program-ready dedicated memory; RAM (Random Access Memory) is a readable and writable memory for storing various information; and a disk is a pre-stored control software and data. . The CPU of the control unit 3 executes a predetermined processing program to perform processing in the heat treatment apparatus 1. Further, as shown in FIG. 8, the control unit 3 includes a pulse wave generator 31 and a waveform setting unit 32. As described above, the waveform setting unit 32 sets the waveform of the pulse wave signal based on the input content from the input unit 33, whereby the pulse wave generator 31 outputs the pulse wave signal to the gate of the IGBT 96.

In addition to the above configuration, in order to prevent excessive temperature rise of the halogen heating unit 4, the flash heating unit 5, and the chamber 6 due to thermal energy generated from the halogen lamp HL and the flash lamp FL during heat treatment of the semiconductor wafer W, the heat treatment apparatus 1 is provided. There are various structures for cooling. For example, a water-cooling tube (not shown) is provided in the wall of the chamber 6. Further, the halogen heating unit 4 and the flash heating unit 5 are air-cooling structures in which a gas flow is formed inside and heat is discharged. Further, a gap between the upper chamber window 63 and the light radiation window 53 is also supplied with air, thereby cooling the flash heating portion 5 and the upper chamber window 63.

Next, the processing procedure of the semiconductor wafer W in the heat treatment apparatus 1 will be described. Here, the semiconductor wafer W to be processed is a semiconductor substrate to which impurities (ions) have been added by ion implantation. The activation of the impurities is performed by the flash irradiation heat treatment (annealing) by the heat treatment apparatus 1. The processing sequence of the heat treatment apparatus 1 described below is performed by the control unit 3 controlling each of the operation mechanisms of the heat treatment apparatus 1.

First, before the heat treatment of the semiconductor wafer W to be processed, the carrier 74 is preheated by the 40 halogen lamps HL of the halogen heating unit 4. In other words, before the first semiconductor wafer W constituting the batch is carried into the chamber 6, the 40 halogen lamps HL of the halogen heating unit 4 are turned on by the control unit 3, and the carrier of the holding portion 7 is heated. 74. A portion of the light that is irradiated from the halogen lamp HL toward the heat treatment space 65 is also absorbed by the carrier 74 of the quartz, whereby the carrier 74 is heated.

The temperature of the elevated temperature carrier 74 is measured by a radiation thermometer 27. However, when the semiconductor wafer W is placed on the carrier 74, since the emitted light radiated from the lower surface of the semiconductor wafer W penetrates the carrier 74 to become an interference light, it is difficult for the radiation thermometer 27 to measure the temperature of the carrier 74. . Before the semiconductor wafer W to be processed is carried into the chamber 6, since the semiconductor wafer W is not placed on the carrier 74, the radiation thermometer 27 can measure the temperature of the carrier 74.

The temperature of the carrier 74 measured by the radiation thermometer 27 is transmitted to the control unit 3. The control unit 3 measures the measurement result of the temperature of the carrier 74 based on the radiation thermometer 27, and feeds back the output of the control halogen lamp HL so that the temperature of the carrier 74 becomes a predetermined temperature. With the halogen lamp HL, the carrier 74 is heated to 200 ° C to 300 ° C, the heating temperature is detailed The description is further detailed later. Further, the control unit 3 waits for the processing of the semiconductor wafer W to be processed to wait until the temperature of the carrier 74 reaches the predetermined temperature. At the point in time when the temperature of the carrier 74 has reached the predetermined temperature, the halogen lamp HL is temporarily extinguished.

Further, in parallel with the preheating of the carrier 74, the valve 84 for supplying air is opened, and the valves 89, 192 for exhaust are opened to start supplying air and exhaust to the chamber 6. When the valve 84 is opened, nitrogen gas is supplied from the gas supply hole 81 to the heat treatment space 65. Further, when the valve 89 is opened, the gas in the chamber 6 is exhausted from the gas exhaust hole 86. Thereby, the nitrogen gas supplied from the upper portion of the heat treatment space 65 in the chamber 6 flows downward, and is exhausted from the lower portion of the heat treatment space 65.

Further, by opening the valve 192, the gas in the chamber 6 is also exhausted from the conveyance opening portion 66, and the atmosphere around the drive portion of the transfer mechanism 10 is also discharged by an exhaust mechanism (not shown). gas. Further, at the time of heat treatment of the semiconductor wafer W in the heat treatment apparatus 1, nitrogen gas is continuously supplied to the heat treatment space 65, and the supply amount thereof is appropriately changed in accordance with the processing steps.

The control unit 3 starts the heat treatment of the first semiconductor wafer W of the batch in the heat treatment apparatus 1 after the temperature of the carrier 74 measured by the radiation thermometer 27 is raised to a predetermined temperature. At the start of the process, the gate valve 185 is opened and the conveyance opening 66 is opened, and the ion-implanted semiconductor wafer W is carried into the heat treatment space 65 in the chamber 6 via the conveyance opening 66 by the conveyance robot outside the apparatus. When the semiconductor wafer W carried in by the transfer robot reaches the position immediately above the holding portion 7, the semiconductor wafer W is stopped. Then, the pair of transfer arms 11 of the transfer mechanism 10 are horizontally moved from the retracted position and raised to the transfer operation position, whereby the take-off and lowering pins 12 protrude from the upper surface of the carrier 74 through the through holes 79 and receive the semiconductor crystal. Round W.

After the semiconductor wafer W is placed on the landing gear 12, the transfer robot is withdrawn from the heat treatment space 65, and the transport opening portion 66 is closed by the gate valve 185. Then, the pair of transfer arms 11 are lowered, whereby the semiconductor wafer W is transferred from the transfer mechanism 10 to the carrier 74 of the holding portion 7, and is held from below in a horizontal posture. The semiconductor wafer W is placed on the carrier 74 with the surface which has been patterned and implanted with impurities as the upper surface. Further, the semiconductor wafer W is placed on the inner side of the five guide pins 76 on the upper surface of the carrier 74. The lowering of one of the carrier arms 74 to the lower side of the carrier 74 is retracted to the retracted position by the horizontal moving mechanism 13, that is, retracted to the inside of the recess 62.

After the semiconductor wafer W is held by the holding portion 7 made of quartz in a horizontal posture from below, the 40 halogen lamps HL of the halogen heating unit 4 are turned on at the same time, and preliminary heating (auxiliary heating) is started. The halogen light emitted from the halogen lamp HL penetrates the lower chamber window 64 formed of quartz and the carrier 74 to the back surface of the semiconductor wafer W (the main surface opposite to the surface). By receiving light from the halogen lamp HL, the semiconductor wafer W is preheated to raise the temperature.

When the preliminary heating is performed by the halogen lamp HL, the temperature of the semiconductor wafer W is measured by the contact thermometer 130. That is, the contact thermometer 130 having the built-in thermocouple contacts the lower surface of the semiconductor wafer W held by the holding portion 7 via the notch portion 77 of the carrier 74 and measures the temperature of the wafer during temperature rise. The temperature of the semiconductor wafer W to be measured is transmitted to the control unit 3. The control unit 3 controls the output of the halogen lamp HL while monitoring whether or not the temperature of the semiconductor wafer W heated by the irradiation of the light from the halogen lamp HL has reached the predetermined preliminary heating temperature T1. In other words, the control unit 3 feedbacks the control of the halogen lamp HL in such a manner that the temperature of the semiconductor wafer W becomes the preliminary heating temperature T1 based on the measured value of the contact thermometer 130. Out. The preliminary heating temperature T1 is set to about 200° C. to 800° C., and is preferably set to about 350° C. to 600° C., in which the impurities added to the semiconductor wafer W are not diffused by heat, and is preferably set to about 350° C. to 600° C. (in this embodiment) In the form, it is 600 ° C). Further, the temperature measurement of the semiconductor wafer W may be performed by the radiation thermometer 120 instead of the contact thermometer 130, or may be performed by the radiation thermometer 120 in addition to the contact thermometer 130.

After the temperature of the semiconductor wafer W reaches the preliminary heating temperature T1, the control unit 3 temporarily maintains the semiconductor wafer W at the preliminary heating temperature T1. Specifically, when the temperature of the semiconductor wafer W measured by the contact thermometer 130 reaches the preliminary heating temperature T1, the control unit 3 adjusts the output of the halogen lamp HL and maintains the temperature of the semiconductor wafer W approximately Prepare heating temperature T1.

The preliminary heating of the halogen lamp HL is performed, whereby the entire semiconductor wafer W is uniformly heated to the preliminary heating temperature T1. In the stage in which the halogen lamp HL is preheated, the temperature of the peripheral portion of the semiconductor wafer W which is more likely to generate heat is lower than that of the central portion, and the arrangement density of the halogen lamp HL in the halogen heating portion 4 is increased. The region facing the peripheral portion is higher than the region facing the central portion of the semiconductor wafer W. Therefore, the amount of light irradiated to the peripheral portion of the semiconductor wafer W where heat generation is likely to occur is increased, and the in-plane temperature distribution of the semiconductor wafer W in the preliminary heating stage can be made uniform. Further, since the inner circumferential surface of the reflection ring 69 attached to the chamber side portion 61 is formed into a mirror surface, the amount of light reflected by the inner circumferential surface of the reflection ring 69 toward the peripheral edge portion of the semiconductor wafer W is increased. The in-plane temperature distribution of the semiconductor wafer W in the preliminary heating stage is made more uniform.

When the temperature of the semiconductor wafer W reaches the preliminary heating temperature T1 and a predetermined time elapses, the flash lamp FL of the flash heating portion 5 is paired with a semiconductor The surface of the bulk wafer W is subjected to flash irradiation. When the flash lamp FL performs flash illumination, the electric charge is accumulated in advance to the capacitor 93 by the power supply unit 95. Then, in a state where the electric charge is accumulated in the capacitor 93, the pulse wave generator 31 of the control unit 3 outputs a wave signal to the IGBT 96, and the IGBT 96 is turned on and off.

The waveform of the pulse wave signal can be specified by inputting a recipe in which the pulse width time (on time) and the pulse wave interval (off time) are sequentially input from the input unit 33 as parameters. When the operator inputs such a recipe from the input unit 33 to the control unit 3, the waveform setting unit 32 of the control unit 3 sets the pulse waveform for repeatedly turning on and off in accordance with the recipe. Next, the pulse wave generator 31 outputs a pulse wave signal in accordance with the pulse waveform set by the waveform setting unit 32. As a result, a pulse signal having a set waveform is applied to the gate of the IGBT 96 to control the on and off driving of the IGBT 96. Specifically, when the pulse signal input to the gate of the IGBT 96 is turned on, the IGBT 96 is turned on; when the pulse signal is turned off, the IGBT 96 is turned off.

Further, in synchronization with the timing at which the pulse wave signal output from the pulse wave generator 31 is turned on, the control unit 3 controls the flip-flop circuit 97 to apply a high voltage (trigger voltage) to the trigger electrode 91. When the capacitor 93 has accumulated electric charge, the pulse signal is input to the gate of the IGBT 96, and a high voltage is applied to the trigger electrode 91 in synchronization with the timing at which the pulse signal is turned on, whereby the pulse signal is sure to be turned on when the pulse signal is turned on. An electric current flows between the electrodes at both ends of the glass tube 92, and the light is emitted by the excitation of the atoms or molecules of the crucible at this time.

Thereby, the 30 flash lamps FL of the flash heating portion 5 emit light, and the surface of the semiconductor wafer W placed on the carrier 74 is irradiated with a flash. Here, in the case where the IGBT 96 is not used but the flash lamp FL is illuminated, it is accumulated in The electric charge of the capacitor 93 is consumed by the primary light emission, and the output waveform from the flash lamp FL is a single pulse having a width of from 0.1 milliseconds to about 10 milliseconds. On the other hand, in the present embodiment, the IGBT 96 belonging to the switching element is connected to the circuit and the pulse signal is output to the gate of the IGBT 96, whereby the charge supply from the capacitor 93 to the flash lamp FL is intermittently interrupted by the IGBT 96. And turn on and off to control the current flowing through the flash lamp FL. As a result, the chopper controls the light emission of the flash lamp FL, and the electric charge accumulated in the capacitor 93 is divided and consumed, and the flash lamp FL repeatedly blinks in an extremely short time. Further, since the next pulse wave is applied to the gate of the IGBT 96 before the current value of the flow circuit is completely "0", the current value is increased again. Therefore, the flash output is not completely changed while the flash FL is repeatedly blinking. 0".

As a result, by controlling the current flowing through the flash lamp FL by turning on and off the IGBT 96, the light emission pattern of the flash lamp FL can be freely specified, and the light emission time and the light emission intensity can be freely adjusted. Specifically, for example, when the ratio of the pulse width time to the pulse wave interval input from the input unit 33 is increased, the current flowing through the flash lamp FL is increased, and the light emission intensity is increased. On the other hand, when the ratio of the pulse width time to the pulse wave interval input from the input unit 33 is decreased, the current flowing through the flash lamp FL is decreased, and the light emission intensity is weak. Further, as long as the ratio of the time of the pulse wave interval input from the input unit 33 to the time of the pulse width is appropriately adjusted, the light emission intensity of the flash lamp FL is maintained constant. Furthermore, the total time of the combination of the time of the pulse width input from the input unit 33 and the time of the pulse wave interval is increased, whereby the current continues to flow to the flash lamp FL for a long time, and the light emission time of the flash lamp FL becomes long. Further, the flash FL has a light emission time of at most 1 second.

Flashing from 30 flash lamps FL, thereby heating the semiconductor crystal by flash Round W. The surface temperature of the semiconductor wafer W heated by the flash is instantaneously increased to a processing temperature T2 of 1000 ° C or higher, and the surface temperature rapidly drops after the impurities implanted in the semiconductor wafer W are activated. Since the light irradiation of the halogen lamp HL is continued after the flash lamp FL emits light, the surface temperature of the semiconductor wafer W is lowered to the vicinity of the preliminary heating temperature T1.

After the completion of the flash heat treatment, the halogen lamp HL is also extinguished after a predetermined time elapses. Thereby, the semiconductor wafer W is rapidly cooled from the preliminary heating temperature T1. The temperature of the semiconductor wafer W during cooling is measured by the contact thermometer 130 or the radiation thermometer 120, and the measurement result is transmitted to the control unit 3. The control unit 3 monitors from the measurement results whether the temperature of the semiconductor wafer W has been cooled to a predetermined temperature. Next, after the temperature of the semiconductor wafer W is cooled to a predetermined value or less, the pair of transfer arms 11 of the transfer mechanism 10 are horizontally moved again from the retracted position and raised to the transfer operation position, whereby the take-off and lowering pins 12 are carried from the load. The upper surface of the body 74 protrudes and receives the heat-treated semiconductor wafer W from the carrier 74. Then, the gate valve 185 opens the locked transport opening 66, and the semiconductor wafer W placed on the landing pin 12 is carried out by the transport robot outside the apparatus, thereby ending the heat treatment of the semiconductor wafer W in the heat treatment apparatus 1. .

Further, typically, the processing of the semiconductor wafer W is performed in batch units. The batch refers to a group of semiconductor wafers W that are subjected to processing of the same content under the same conditions. In the heat treatment apparatus 1 of the present embodiment, the plurality of semiconductor wafers W constituting the batch are sequentially carried into the chamber 6 one by one and heat-treated.

Here, in the case where the batch processing is started without directly performing the preheating of the carrier 74 in the heat treatment apparatus 1 that has not been temporarily processed, the first semiconductor wafer W of the batch is carried to about room temperature. Chamber 6 goes in Line flash heat treatment. Such a case is, for example, a case where the initial batch is processed after the heat treatment device 1 is started after maintenance, and a long time after the previous batch is processed. At the time of the heat treatment, heat transfer occurs in the chamber structure such as the carrier 74 from the semiconductor wafer W that has been heated. Therefore, the carrier 74 at the initial room temperature is slowed down as the number of processed semiconductor wafers W increases. Slowly accumulate heat and heat up.

FIG. 9 is a view showing the relationship between the number of processed semiconductor wafers W and the temperature of the carrier 74. The carrier 74 which is room temperature before the start of the process is gradually heated by the heat transfer from the semiconductor wafer W as the number of processed semiconductor wafers W increases, and then the semiconductor wafer of the tenth sheet is completed. At the time of heat treatment of the circle W, the temperature of the carrier 74 reaches a certain stable temperature Ts. In the carrier 74 that has reached the stable temperature Ts, the amount of heat transfer from the semiconductor wafer W toward the carrier 74 is equalized to the amount of heat released from the carrier 74. Until the temperature of the carrier 74 reaches the stable temperature Ts, since the amount of heat transfer from the semiconductor wafer W is more than the amount of heat radiated from the carrier 74, the temperature of the carrier 74 is processed along with the semiconductor wafer W. The number increases and slowly accumulates heat and rises. On the other hand, after the temperature of the carrier 74 reaches the stable temperature Ts, since the amount of heat transfer from the semiconductor wafer W and the amount of heat radiation from the carrier 74 are equalized, the temperature of the carrier 74 is maintained at a certain stable temperature Ts. .

As described above, when the processing is started in the chamber 6 at room temperature, there is a case where the temperature history is inconsistent because the initial semiconductor wafer W of the batch and the semiconductor wafer W in the middle are supported by the carrier 74 of different temperatures. Further, there is a case where the initial semiconductor wafer W is supported by the low-temperature carrier 74 and subjected to flash heat treatment to cause warpage of the wafer. Therefore, as described above, in the related art, the simulation operation is performed before the start of the batch processing, and the simulation operation is performed by loading the dummy wafer not to be processed into the chamber 6. The flash heat treatment is performed in the same manner as the semiconductor wafer W to be processed, and the chamber structure such as the carrier 74 is heated to a stable temperature Ts.

In the present embodiment, the preheating carrier 74 is irradiated with light from the halogen lamp HL before the first semiconductor wafer W of the batch is carried into the chamber 6. At this time, the control unit 3 controls the output of the halogen lamp HL such that the temperature of the carrier 74 reaches the stable temperature Ts based on the measurement result of the temperature of the carrier 74 measured by the radiation thermometer 27. Specifically, the stability temperature Ts is obtained in advance by experiments, simulations, or the like, and is stored in advance in the memory unit of the control unit 3. Next, the control unit 3 controls the output of the halogen lamp HL such that the temperature of the carrier 74 measured by the radiation thermometer 27 reaches the stable temperature Ts, and performs light irradiation heating to the carrier 74.

The stable temperature Ts does not require the preheating of the carrier 74, but the temperature of the carrier 74 is raised and becomes a certain time by the continuous irradiation of a plurality of semiconductor wafers W in the chamber 6 by the light irradiation heating. The temperature of the body 74. The stable temperature Ts differs depending on the preliminary heating temperature T1 of the semiconductor wafer W constituting the batch, and is 200 ° C to 300 ° C. Next, after the temperature of the carrier 74 is raised to the stable temperature Ts, heat treatment is performed on the first semiconductor wafer W of the batch.

Before the heat treatment of the first semiconductor wafer W of the batch is started, the carrier 74 is heated to a stable temperature Ts by irradiation with light from the halogen lamp HL, thereby constituting all of the semiconductor wafers of the batch. It is supported by the carrier 74 of the same temperature, and the temperature history can be set to be uniform. Further, since the initial semiconductor wafer W of the batch is also supported by the carrier 74 which has been heated up to the stable temperature Ts, the wafer warpage caused by the temperature difference between the carrier 74 and the semiconductor wafer W can be prevented. song. As a result, it is possible to omit the heat treatment of a plurality of dummy wafers in the past. Since the simulation operation is performed, the substrate processing apparatus 1 can be used efficiently.

<Second embodiment>

Next, a second embodiment of the present invention will be described. The overall schematic configuration of the heat treatment apparatus according to the second embodiment and the processing sequence of the semiconductor wafer W are approximately the same as those of the first embodiment. However, the number of radiation thermometers for measuring the temperature of the carrier 74 is different. In the first embodiment, a radiation thermometer 27 for measuring the temperature of the central portion of the carrier 74 is provided. In contrast, in the second embodiment, a plurality of portions for measuring the carrier 74 are provided. The temperature of the radiation thermometer.

Specifically, in the second embodiment, a total of three radiation thermometers are provided, which are radiation thermometers for measuring the temperature of the central portion of the carrier 74, and for measuring the peripheral portion of the carrier 74. A radiation thermometer for temperature and a radiation thermometer for measuring the temperature of the intermediate portion between the central portion and the peripheral portion of the carrier 74. Further, in the second embodiment, each of the plurality of temperature measuring portions included in the carrier 74 controls the irradiation of light from the halogen heating portion 4. That is, the zone controls the temperature of the carrier 74.

FIG. 10 is a view showing an example of section control of the temperature of the carrier 74. The slightly circular carrier 74 is concentrically divided into three regions of a central section CZ, an intermediate section MZ, and a peripheral section EZ. The above three radiation thermometers measure the temperatures of the central section CZ, the intermediate section MZ, and the peripheral section EZ, respectively. Next, the control unit 3 measures the temperatures of the central section CZ, the intermediate section MZ, and the peripheral section EZ measured by the three radiation thermometers, with the central section CZ, the intermediate section MZ, and the peripheral section EZ. The temperature of the person reaches the steady temperature Ts to control the output of the halogen lamp HL. Since the output of 40 halogen lamps HL can be individually Since the adjustment is performed, the control unit 3 can adjust only the output of the halogen lamp HL corresponding to each of the center segment CZ, the intermediate segment MZ, and the peripheral segment EZ. For example, in the case where the temperature of the peripheral section EZ of the carrier 74 is lower than the temperatures of the central section CZ and the intermediate section MZ, the halogen lamp HL corresponding to the peripheral section EZ is increased (located in the peripheral section EZ) The output of the halogen lamp HL) below increases the amount of light that strikes the peripheral section EZ. Thereby, the peripheral section EZ of the carrier 74 is reinforced and becomes the same temperature as the center section CZ and the intermediate section MZ, and the entire carrier 74 is uniformly heated to the stable temperature Ts.

The other configuration of the second embodiment is the same as that of the first embodiment except that a plurality of radiation thermometers are provided and the temperature of the carrier 74 is controlled. In the second embodiment, it is also possible to raise the temperature of the carrier 74 to the stable temperature Ts by irradiation with light from the halogen lamp HL before the heat treatment of the first semiconductor wafer W of the batch is started. The entire semiconductor wafer W of the batch is supported by the carrier 74 of the same temperature, and the temperature history is set to be uniform. Further, since the initial semiconductor wafer W of the batch is also supported by the carrier 74 which has been heated up to the stable temperature Ts, the wafer warpage caused by the temperature difference between the carrier 74 and the semiconductor wafer W can be prevented. song. As a result, since the simulation operation for heat-processing the plurality of dummy wafers in the related art can be omitted, the substrate processing apparatus 1 can be used efficiently. Further, in the second embodiment, since a plurality of radiation thermometers are provided and the temperature of the carrier 74 is controlled in sections, the temperature of the carrier 74 can be uniformly increased and the temperature can be uniformly increased.

<variation>

Although the embodiments of the present invention have been described above, the present invention can be variously modified in addition to the above-described embodiments without departing from the spirit and scope of the invention. For example, in each of the above embodiments, The carrier 74 is heated by the halogen lamp HL for heating the semiconductor wafer W. However, the carrier 74 is not limited thereto, and the carrier 74 for heating the quartz by a dedicated heating means such as an impedance heating type heater may be used.

Further, in each of the above embodiments, the temperature of the carrier 74 is measured by a radiation thermometer, but the temperature of the carrier may be measured by a contact thermometer in which a thermocouple is incorporated.

Further, there is a case where it is not easy to accurately measure the temperature of the quartz carrier 74 by the radiation thermometer 27, and there is a case where it is not necessary to accurately measure the temperature of the carrier 74. That is, as long as the temperature of the carrier 74 reaches the stable temperature Ts, it is sufficient that the control unit 3 has a temperature difference of zero between the temperature of the carrier 74 measured by the radiation thermometer 27 and the stable temperature Ts. The mode controls the output of the halogen lamp HL. However, in this case, it is necessary to previously measure the stable temperature Ts with the same radiation thermometer 27 by experiments in advance. Further, the control unit 3 may control the halogen in such a manner that the output of the radiation thermometer 27 when the stable temperature Ts has been measured coincides with the output of the radiation thermometer 27 that has measured the temperature of the preheated carrier 74. The output of the lamp HL.

Further, in the second embodiment, although three radiation thermometers are provided and the carrier 74 is divided into three sections and section control is performed, the present invention is not limited thereto, and two or more plural temperature senses are provided. The detector performs heating control in each of the regions including the plurality of temperature measuring portions.

Further, in the second embodiment, the control is performed such that all the segments of the carrier 74 have the same temperature, but each segment of the carrier 74 may have a different temperature depending on the need of the process. get on Heating control. For example, in order to prevent the relative temperature drop of the peripheral portion of the semiconductor wafer W during preliminary heating, the peripheral portion EZ of the carrier 74 may be controlled to be higher than the central portion CZ and the intermediate portion MZ. Output.

Further, in each of the above embodiments, the IGBT 96 is not necessarily an essential member because the IGBT 96 controls the light emission of the flash lamp FL. Even in the case where the flash lamp FL is simply emitted without using the IGBT 96, by heating the carrier 74 to the stable temperature Ts before starting the heat treatment for the first semiconductor wafer W of the batch, the above can be obtained. The same effect of the embodiment.

Further, in each of the above embodiments, the flash heating unit 5 is provided with 30 flashes FL, but the present invention is not limited thereto, and the number of the flash lamps FL may be any number. In addition, the flash FL is not limited to the xenon flash, and may be a krypton flash. In addition, the number of the halogen lamps HL included in the halogen heating unit 4 is not limited to 40, and may be any number as long as it is arranged in plural numbers in the upper stage and the lower stage.

In addition, the substrate to be processed by the heat treatment apparatus of the present invention is not limited to the semiconductor wafer, and may be a glass substrate for a flat panel display such as a liquid crystal display device or a substrate for a solar cell. In addition, the technique of the present invention can also be applied to heat treatment of a high dielectric gate insulating film (also known as a high-k (high dielectric) film), bonding of a metal to germanium, or crystallization of polysilicon. Chemical.

1‧‧‧ Heat treatment unit

3‧‧‧Control Department

4‧‧‧Halogen heating department

5‧‧‧Flash heating department

6‧‧‧ chamber

7‧‧‧ Keeping Department

10‧‧‧Transportation mechanism

27‧‧‧radiation thermometer

41, 51‧‧‧ frame

43, 52‧‧‧ reflector

53‧‧‧Lighting window

61‧‧‧ side of the chamber

62‧‧‧ recess

63‧‧‧Upper chamber window

64‧‧‧Lower chamber window

65‧‧‧ Heat treatment space

66‧‧‧Transportation opening

68, 69‧‧‧ reflection ring

74‧‧‧Carrier

81‧‧‧ gas supply hole

82, 87‧‧‧ buffer space

83‧‧‧ gas supply pipe

84, 89, 192‧‧ ‧ valves

85‧‧‧Nitrogen supply

86‧‧‧ gas vents

88, 191‧‧‧ gas exhaust pipe

185‧‧‧ gate valve

190‧‧‧Exhaust Department

FL‧‧‧Flash

HL‧‧‧ halogen lamp

W‧‧‧Semiconductor Wafer

Claims (10)

A heat treatment method for irradiating a substrate with light to heat the substrate; the heat treatment method includes: carrying in a step of carrying the substrate into the chamber and placing it on the carrier; and the step of irradiating the light is carried in the foregoing The substrate of the carrier is irradiated with light; the temperature measuring step is to measure the temperature of the carrier before the initial substrate of the batch is carried into the chamber; and the heating step is to heat the carrier according to the measurement result of the temperature measuring step . The heat treatment method according to claim 1, wherein the plurality of substrates of the batch are continuously irradiated with light and heated without heating the carrier, whereby the temperature of the carrier is increased and the carrier is fixed for a certain period of time. The temperature of the body is set to a stable temperature; in the heating step, the carrier is heated in such a manner that the temperature of the carrier reaches the stable temperature. The heat treatment method according to claim 1, wherein the temperature of the plurality of portions of the carrier is measured in the temperature measuring step; and each of the regions including the plurality of portions is heated and controlled in the heating step. The heat treatment method according to claim 1, wherein in the light irradiation step, the substrate is irradiated with a flash from a side of the chamber by a flash lamp. The heat treatment method according to claim 4, wherein in the light irradiation step, the substrate is further irradiated with light by a halogen lamp from the other side of the chamber; in the heating step, by irradiation with light from a halogen lamp The aforementioned carrier is heated. A heat treatment device for heating a substrate by irradiating light onto a substrate; the heat treatment device comprising: a chamber for accommodating a substrate; and a carrier disposed in the chamber for mounting and supporting the substrate; the light illuminating portion And irradiating light to the substrate placed on the carrier; the temperature measuring unit measures the temperature of the carrier; and the control unit is based on the temperature before the first substrate of the batch is carried into the chamber As a result of measuring the temperature of the carrier measured by the measuring unit, the light illuminating unit is controlled such that the light is irradiated from the light illuminating unit to heat the carrier. The heat treatment apparatus according to claim 6, wherein the plurality of substrates of the batch are continuously irradiated with light from the light irradiation unit and heated without heating the carrier, whereby the temperature of the carrier is heated. The temperature of the carrier is set to a stable temperature when the degree is increased, and the control unit controls the light irradiation unit such that the temperature of the carrier reaches the stable temperature. The heat treatment device according to claim 6, wherein the temperature measuring unit includes: a plurality of temperature sensors for measuring a temperature of a plurality of portions of the carrier; and the control unit includes the plurality of portions Each of the regions controls the irradiation of light from the aforementioned illuminating portion. The heat treatment apparatus according to claim 6, wherein the light irradiation unit includes a flash lamp that illuminates the substrate from a side of the chamber. The heat treatment device according to claim 9, wherein the light irradiation unit further comprises: a halogen lamp that irradiates the substrate with light from the other side of the chamber; and heats the carrier by irradiation with light from the halogen lamp .